Recent market research studies have shown that a growing number of users rely solely on their portable device such as smart phones as the primary interface for accessing and programming their home automation products such as thermostats. However, the majority if not all of these products sold in the market today still incorporate the traditional keyboard/display interface, especially for thermostats. In a multi-zone climate control system where multiple thermostats are deployed, the less frequently used keyboard/display interface is replicated in each thermostat which unnecessarily increases the overall cost of the system. An obvious solution would be to design wireless-only thermostats without the keyboard/display interface. The drawback of this simplistic solution is that every time a wireless thermostat, or in general any wireless device such as a wirelessly controlled light switch, etc., is added to the wireless network, the wireless router allocates a fixed portion of the available wireless bandwidth to the device despite that these devices operate at a very low data rate. Therefore, using wireless-only thermostats, light switches, etc. will waste valuable wireless bandwidth that is better reserved for applications that require high data rate such as video streaming.
It has been suggested that using the power line as a communication medium instead of the wireless network will free up wireless bandwidth allocated to low data rate devices such as thermostats. To the best of our knowledge we are not aware of any commercial product that takes advantage of power line networking in order to reduce the hogging of the wireless bandwidth by low data rate devices. In fact, all power line products introduced up to date combine power line access with wireless access in every single device which obviates any advantage of using the power line as discussed above. In addition, the keyboard/display interface is also replicated, more likely than not, in every single device.